Dovetails in thick stock :UPDATED

DPatton · December 19, 2018, 07:44:58 PM

I want to do some dovetail joints in 1 1/2" thick stock slab material, but haven't been able to find a dovetail bit that will cut 1 1/2 deep. I would like to hear if anyone has experience with dovetails joints in stock this thick and if there is a dovetail router bit out there for this depth of joint.

PA_Walnut · December 19, 2018, 07:52:22 PM

Best dovetail bit is a nice fine-tooth saw and a chisel! :D

Brad_bb · December 19, 2018, 08:40:26 PM

Yes, don't be afraid to do hand cut dovetails. I just built some louvered doors where the frame of the door was 2x6 barn wood material that I dovetailed together.

I used the divider method to layout the dove tails. A good dovetail saw makes it pretty easy to saw them out very straight.

Laying Out Dovetails with Christopher Schwarz - YouTube
PS, you don't need two dividers.

TIP: If you're making a frame like my door frame, or a cabinet frame etc, put your pins on the long pieces, not the shorter ones. It will make assembly much easier (and cutting will be easier).

LeeB · December 19, 2018, 10:29:35 PM

Maybe tails on the long pieces Brad?

DPatton · December 20, 2018, 10:11:02 PM

I hear ya on the hand cut dovetails but not for this piece. I want them perfect as they will be an important part of the focal point on the piece I want to build. It may be possible that I go with a 3/4 depth half blind dovetail connection but I'm not sure I would be happy with it. I would really like to find a dovetail router bit that will go the full 1 1/2" depth.

Dan_Shade · December 20, 2018, 11:09:09 PM

Look up how you can do them with your table saw.

You can also use a bandsaw

coalsmok · December 21, 2018, 07:04:33 AM

Get yourself some scrap and lay out a half dozen or so individual joints and practice cutting them. I have done them on a bandsaw if you are against using a lot of hand tools.
I really doubt you find a router bit for that size dovetail.

DPatton · December 21, 2018, 11:20:54 AM

Quote from: Dan_Shade on December 20, 2018, 11:09:09 PM
Look up how you can do them with your table saw.

You can also use a bandsaw

Problem is the piece I am working with is 7' long and 22"-26" wide X 1 1/2" thick. Its a little problematic to handle doing the cuts on a table saw or band saw. This joint will be at the 90* bend in a live edge waterfall desk top. I also plan to round over the 90* dovetailed corner with an 1 1/2" radius so the joints must be accurate and tight all the way through the cut. I figure if such a bit exists the guys on this forum would likely know about it.

Dan_Shade · December 21, 2018, 11:53:15 AM

If that's what I wanted, I would do it by hand, then round it over, and then kerf in the gaps with thin shims to fill in any gaps. Finish by sanding off level.

btulloh · December 21, 2018, 11:56:55 AM

Mentioned above - cut 'em by hand. If that's not comfortable to you it's high time to start. Practice on a some scrap, like mentioned. A well sharpened saw is your friend. Sharp chisels for paring to clean. Don't use your paring chisel to chop the waste. A Japanese pull saw works good for thick stock and they are not expensive compared to most good saws. You can get one with rip teeth on one side and crosscut on the other side. It's a great skill to develop and doesn't take that long to get competent. You can cut them faster by hand than the time it takes to set up to rout them, even if you could find a bit.

Using a saw that's not sharpened and set properly is a recipe for frustration. But that's true across the board. I don't know any good way to do this with a router on something that thick.

Just my .02

low_48 · December 21, 2018, 11:06:09 PM

Keller sells a kit that does up to 1 1/4" thick stock. Keller dovetail jigs : Models : 3600

Plus there is this option if you could cut a miter joint on the stock. https://www.infinitytools.com/complete-tapered-dovetail-spline-systems

Brad_bb · December 22, 2018, 12:08:06 AM

Sounds like you're building a slab table With the same material for the legs on each side or one side, kind of like a waterfall table?

DPatton · December 22, 2018, 05:58:44 AM

Quote from: Brad_bb on December 22, 2018, 12:08:06 AM
Sounds like you're building a slab table With the same material for the legs on each side or one side, kind of like a waterfall table?

Yes, a live edge waterfall desk. My idea is to turn down one end full length as a leg and have either metal or wood accent leg at the other end. A large round over at the dovetails gives a really amazing look when done right.

DPatton · December 22, 2018, 06:20:15 AM

Quote from: low_48 on December 21, 2018, 11:06:09 PM
Keller sells a kit that does up to 1 1/4" thick stock. Keller dovetail jigs : Models : 3600

Plus there is this option if you could cut a miter joint on the stock. https://www.infinitytools.com/complete-tapered-dovetail-spline-systems

Thanks Low_48. If I took my stock material down to 1 1/4" thickness this could work. I had also been considering spline joints of some type if I couldn't find the length of bit I want. There are some interesting things one can do with dovetailed spline connections too.

DPatton · January 06, 2019, 11:58:07 PM

Well I knew you guys would be able to lead me in the right direction, so after reading all of your replies and exhausting my searches for a router bit I started looking for an alternate idea for the 90* waterfall edge joint. I appreciate everybody's input and advice. The piece I am working on is a donation piece for this years Ducks Unlimited Banquet. I considered hand cutting joints but just couldn't convince myself I could be satisfied with it. So I ended up working with low_48's idea on a mitered spline joint system. Below are some photos of the spline joint system I came up with.

The table top and waterfall leg are from an elm slab I've been drying in my basement.

Z

The splines are walnut. I think they provide some contrast and add a bit of interest to the rounded over 90* joint.

Routing and installing the splines was all a new experience to me. I found the dovetail router bit and angled router cuts less than friendly to work with but was able salvage a couple of router mistakes and keep the splines reasonably even and consistent.

Next was another new challenge for me. Adding walnut butterflies at a couple of checks and filling knots, checks, and voids with epoxy.

Z

Some of you by now might think I had a plan on how I wanted to build this table, but that really couldn't be further from the truth. See I had no Idea how I planned to support the other end of this thing. After brainstorming and looking on line for some time I was pretty sure I was going to go with a pair of Leg Rite Queen Ann style legs for the other end. Then my daughter said "Dad I think some nice curved walnut legs to match the walnut butterflies would look nice". After thinking it over for a minute and remembering a certain piece of walnut I had out in the garden shed I looked her straight in the eyes and sarcastically said "Thanks, you just cost me a lot of hours of extra work" :D :D :D below is that piece of walnut and the rough layout of a pair of curved legs ready to be cut out. I simply used the natural curvature of the live edge on the left side to layout both legs. The narrow strip in the middle between the legs had a check in it I was trying to avoid.

W

I cut them out with a jig saw, clamped them together side by side and started sanding the curved edges out to match each other exactly. Below is a photo of the two legs sanded smooth with edges rounded and ready for mortises to be cut at cross member locations. The elm cross members are just to the left of the legs in the photo.

That's all for now. I will keep you posted on upcoming progress.

WLC · January 07, 2019, 01:23:31 AM

Beautiful!!!!

doc henderson · January 07, 2019, 03:38:22 AM

In the NE, they have referred to elm as "exotic hardwood" and commanded a great price. That is cool and glad to see someone using what is in our area. Not everything has to be made out of oak. Sharp!!!

WDH · January 07, 2019, 08:03:55 AM

Mighty fine work, there, Sir.

DPatton · March 03, 2019, 09:03:49 AM

Thanks for the positive comments guys! The legs were prepped with four shallow mortises to accept the tenon on each end of the cross members then glued, and screwed with wood plugs added to cover fastener locations. Once the legs were assembled they were mortised and glued into the underside of the table top slab.

Based on some of my reading here on the FF. I had decided to give a 100% tung oil finish a try on this piece. I like the way the tung oil made the typically lack luster grain of the Elm really pop out, and it gives walnut just what it needs for a dark rich natural look.

Here is a underside pic of the legs fully assembled onto the table. At this point I had several of the 6 applications of tung oil finish on.

A view of the waterfall end of the table with the walnut dovetail splines and butterflies.

W

doc henderson · March 03, 2019, 09:36:15 AM

Very impressive!!! who ever gets that will be one lucky duck!!! should raise funds for a good organization.

WDH · March 03, 2019, 11:43:13 AM

A signature piece.

samandothers · March 03, 2019, 12:28:07 PM

Very nicely done! Very creative and well executed!

DPatton · March 03, 2019, 10:51:23 PM

UPDATED:

The waterfall table went to my local Ducks Unlimited Chapters auction held last evening. I have been apprehensive for the past several weeks that it may not be what most typical buyers are looking for with the tung oil finish. Even though I like what the tung oil did to bring out the grain and color variations in the wood I've just been concerned that it wouldn't be what trips the triggers of the bidders at this event.
The crowd last evening was quite different than normal too as it was a smaller than usual group with many of the regular supporters missing the event this year. Meaning if you were a buyer it was a good night for deals on the auction block. I witnessed numerous items that went for half price and even less than what they typically go for at the annual event.
The organizers of the event held the table back as one of the last five items to be auctioned off, and I'm happy to say there was at least a few bidders that were interested. When the bidding stopped the table had provided a nice return of just under $700.00 toward conserving wetlands. Maybe not as high as I had hoped but definitely what I thought was a fair value and enough to make me proud of my contribution. I really enjoy giving to this organization so today has been spent reflecting on the build and dreaming up ideas for next years piece.

doc henderson · March 04, 2019, 09:12:32 AM

you made money for the organization, and like raising kids you will always remember the experience, and learned about new techniques. as well have made a name for yourself. next year people will be looking to see what is next. I use to sponsor the pictures and pay upfront for the frame and pic., then it was auctioned off and brought same money. I take more pride in making something. congrats!